Multi-Circuit Seal Plates

ABSTRACT

An end effector assembly adapted to couple to an electrosurgical instrument, the end effector assembly including a pair of opposing jaw members pivotably attached about a pivot member and moveable from a first spaced position to a second grasping position. Each jaw member includes a jaw housing and a seal plate formed on an inner surface of the jaw member including at least two seal plate segments extending along a substantial portion of the length of the jaw members. An insulating member is positioned between adjacent seal plate segments and configured to provide electrical isolation between adjacent seal plate segments. Each sealing plate segment is adapted to selectively connect to an electrosurgical energy source and form part of an electrosurgical energy delivery circuit.

BACKGROUND

1. Technical Field

The present disclosure relates to electrosurgical instruments used foropen and endoscopic surgical procedures. More particularly, the presentdisclosure relates to an apparatus with multi-circuit seal plates,method of manufacturing multi-circuit seal plates and methods of sealingtissue with multi-circuit seal plates.

2. Description of Related Art

Electrosurgical forceps utilize mechanical clamping action along withelectrical energy to effect hemostasis on the clamped tissue. Theforceps (open, laparoscopic or endoscopic) include electrosurgicalsealing plates that engage tissue and deliver electrosurgical energy tothe engaged tissue. By controlling the intensity, frequency and durationof the electrosurgical energy applied through the sealing plates totissue, the surgeon can coagulate, cauterize, and/or seal tissue.

During an electrosurgical procedure, seal plates deliver electrosurgicalenergy and/or heat to tissue. Ideally, the seal plates evenly distributeenergy and uniformly heats tissue positioned between the seal plates.The seal plates and varying tissue properties and thicknesses can resultin uneven distribution of energy, uneven heating and generation of hotzones within or between the sealing plates. As a result, the unevendistributed of energy may result in a longer duration sealing procedureand/or may result in a low-quality seal.

Additionally, a surgical procedure may often require several energydelivery sequences. The seal plates are heated during eachelectrosurgical energy delivery sequence and the time between eachelectrosurgical energy delivery may be insufficient to cool the sealplates. As such, thermal energy may accumulate during subsequent energydelivery sequences thereby resulting in a higher than desiredtemperature for the seal plates and a higher than desired temperature oftissue positioned between the seal plates.

SUMMARY

According to an aspect of the present disclosure, an end effectorassembly adapted to couple to an electrosurgical instrument includes apair of opposing jaw members pivotably attached about a pivot member andmoveable from a first spaced position to a second grasping position.Each jaw member includes a jaw housing and a seal plate formed on aninner surface of the jaw member. The seal plate includes at least twoseal plate segments extending along a substantial portion of the lengthof the jaw members. The jaw member also includes an insulating memberpositioned between adjacent seal plate segments and configured toprovide electrical isolation between adjacent seal plate segments. Eachsealing plate segment is adapted to selectively connect to anelectrosurgical energy source and form part of an electrosurgical energydelivery circuit.

Each jaw member may also include a seal plate mount configured tooperably couple the seal plate and the jaw housing and furtherconfigured to electrically couple each of the two or more seal platesegments to an electrosurgical energy source. The seal plate mount mayinclude one or more switch circuit boards disposed on and operablycoupled atop each seal plate.

Each seal plate may include a first seal plate segment, a second sealplate segment and a middle seal plate segment operably coupled betweenthe first and second seal plate segments. A first insulating member ispositioned between the first seal plate segment and the middle sealplate segment to provide electrical isolation therebetween. A secondinsulating member is positioned between the second seal plate segmentand the middle seal plate segment to provide electrical isolationtherebetween. The first, second and middle seal plate segments on eachopposing jaw member form a planar sealing surface. Each of the first,second and middle seal plate segments is configured to selectively formpart of an electrosurgical energy delivery circuit for sealing tissuepositioned between the pair of opposing jaw members.

The middle seal plate segments may be configured to form part of anelectrosurgical energy delivery circuit for cutting tissue positionedbetween the pair of opposing jaw members. A middle seal plate segmentmay include a geometry that is raised with respect to the planar sealingsurface. The geometry may form a ridge or may include a radius ofcurvature.

According to a further aspect of the present disclosure, anelectrosurgical instrument includes a housing, a handle assembly, ashaft having a proximal end and a distal end, the proximal end operablycoupled to the housing and the distal end operably coupled to an endeffector assembly. The end effector assembly includes a pair of opposingjaw members pivotably attached about a pivot member and moveable from afirst, spaced, position to a second, grasping, position. Each jaw memberincludes a jaw housing, a seal plate formed on an inner surface of thejaw member including at least two seal plate segments extending along asubstantial portion of the length of the jaw members and an insulatingmember positioned between adjacent seal plate segments. The insulatingmembers are configured to provide electrical isolation between adjacentseal plate segments. Each sealing plate segment is adapted toselectively connect to an electrosurgical energy source and form part ofan electrosurgical energy delivery circuit.

The electrosurgical instrument may further include a seal plate mountformed on each of the pair of opposing jaw members. The seal plate mountis configured to operably couple the seal plate and the jaw housing andelectrically couple each of the two or more seal plate segments to anelectrosurgical energy source. A switch, formed in the housing, mayoperably couple to the seal plate mount. The seal plate mount mayfurther include a circuit board that includes at least two circuit boardswitches operably coupled to the switch. The switch and circuit boardswitches may selectively couple each of the seal plate segments to theelectrosurgical energy source.

According to a further aspect of the present disclosure, anelectrosurgical instrument includes a first and second shafts pivotablyattached to one another about a common pivot. Each shaft includes a jawmember on a distal end thereof that includes a jaw housing, a seal plateand an insulating member. Each seal plate is formed on an inner surfaceof the respective jaw member and includes two or more seal platesegments extending along a substantial portion of the length of the jawmember. An insulating member is positioned between adjacent seal platesegments and configured to provide electrical isolation therebetween.Each seal plate segment is adapted to selectively connect to anelectrosurgical energy source and form part of an electrosurgical energydelivery circuit.

BRIEF DESCRIPTION OF THE DRAWINGS

Various aspects of the subject instrument are described herein withreference to the drawings wherein:

FIG. 1A is a perspective view of an endoscopic forceps having an endeffector including multi-circuit seal plates in accordance with anaspect of the present disclosure;

FIG. 1B is a perspective view of forceps for use in an open surgicalprocedure having an end effector including multi-circuit seal plates inaccordance with an aspect of the present disclosure;

FIG. 2A is a perspective view of the end effector for use with theforceps of FIG. 1A and FIG. 1B in an open condition and includingmulti-circuit seal plates;

FIG. 2B is a front, cross-sectional view of the end effector of FIG. 2Ain a closed condition;

FIG. 3A is a perspective view of an end effector for use with theforceps of FIG. 1A and FIG. 1B in an open condition and includingmulti-circuit seal plates in accordance with a further aspect of thepresent disclosure;

FIG. 3B is a front, cross-sectional view of the end effector of FIG. 3Ain a closed condition;

FIG. 4A is a perspective view of an end effector for use with theforceps of FIG. 1A and FIG. 1B in an open condition and includingmulti-circuit seal plates in accordance with a further aspect of thepresent disclosure;

FIG. 4B is a front, cross-sectional view of the end effector of FIG. 4Ain a closed condition;

FIG. 5A is a perspective view of an end effector for use with theforceps of FIG. 1A and FIG. 1B in an open condition and includingmulti-circuit seal plates in accordance with a further aspect of thepresent disclosure;

FIG. 5B is a front, cross-sectional view of the end effector of FIG. 5Ain a closed condition; and

FIG. 6 is a schematic block diagram of an electrosurgical system for usewith an end effector including multi-circuit seal plates according to afurther aspect of the present disclosure.

DETAILED DESCRIPTION

Embodiments of the present disclosure are described in detail withreference to the drawing figures wherein like reference numeralsidentify similar or identical elements. As used herein, the term“distal” refers to the portion that is being described which is furtherfrom a user, while the term “proximal” refers to the portion that isbeing described which is closer to a user.

In accordance with the present disclosure, generally an end effectorincludes an upper seal plate and a lower seal plate describedcollectively as seal plates. The seal plates according to the presentdisclosure are manufactured to include a plurality of seal platesegments. The seal plate segments are configured to be selectivelyenergized by a control circuit. Alternatively, two or more seal platesegments may be configured to be simultaneously energized by one or moreelectrical circuits. In this manner, tissue is selectively treated byone or more the individual seal plate segments or sequentially treatedby one or more of the circuits that connect to the various seal platesegments. As such, the end effectors according to the present disclosureare configured and/or customized such that the tissue, or separateportions of the tissue, grasped between the jaw members, may beselectively treated.

Referring now to the figures, FIG. 1A depicts an endoscopic forceps 10for use in connection with endoscopic surgical procedures and FIG. 1Bdepicts an open forceps 10′ for use in traditional open surgicalprocedures. For the purposes herein, either an endoscopic instrument,e.g., forceps 10, or an open surgery instrument, e.g., forceps 10′, mayutilize and end effector in accordance with the present disclosure.Obviously, different electrical, optical and mechanical connections andconsiderations apply to each particular type of instrument; however, thenovel aspects with respect to the end effector assemblies describedherein and their operating characteristics remain generally consistentwith respect to both the endoscopic or open surgery designs.

Turning now to FIG. 1A, the endoscopic forceps 10 is coupled to anelectrosurgical generator 40, or other suitable surgical energy source.Forceps 10 is adapted to seal tissue using radiofrequency (RF) energy orother suitable electrosurgical energy. Generator 40 is configured toprovide electrosurgical energy at any suitable RF frequency.

Forceps 10 is coupled to generator 40 via a cable 34. Cable 34 isconfigured to transmit one or more RF energy signals and/or energycontrol signals between the generator 40 and the forceps 10. Forceps 10may alternatively be configured as a self-contained instrument thatincludes the functionality of the generator 40 within the forceps 10(e.g., an energy source, a signal generator, a control circuit, etc. . .. ). For example, forceps 10 may include a battery (not explicitlyshown) that provides electrical energy, an RF generator (40) connectedto the battery and configured to generate one or more RF energy signalsand a microprocessor to perform measurement and control functions and toselectively delivery one or more RF energy signals to the end effector100.

Forceps 10 include a housing 20, a handle assembly 22, a rotatingassembly 28, a trigger assembly 30 and an end effector 100. Forceps 10further include a shaft 12 having a distal end 14 configured to engagethe end effector 100 and a proximal end 16 configured to engage thehousing 20 and/or the rotating assembly 28. Cable 34 connects to wires(not explicitly shown) in the housing 20 that extend through the housing20, shaft 12 and terminate in the end effector 100 thereby providing oneor more electrical energy signals to the upper and lower sealing plates112, 122.

Handle assembly 22 includes a fixed handle 26 and a moveable handle 24.Fixed handle 26 is integrally associated with housing 20 and moveablehandle 24 is moveable relative to the fixed handle 26 to actuate the endeffector 100 between an open condition and a closed condition and tograsp and treat tissue positioned therebetween. Rotating assembly 28 isrotatable in a clockwise and a counter-clockwise rotation to rotate endeffector 100 about longitudinal axis “X-X”. Housing 20 houses theinternal working components of forceps 10.

End effector 100 includes upper and lower jaw members 110 and 120 arepivotable about a pivot 19 and are moveable between a first conditionwherein jaw members 110 and 120 are closed and mutually cooperate tograsp, seal and/or sense tissue therebetween (See FIGS. 1A and 1B) and asecond condition wherein the jaw members 110 and 120 are spaced relativeto another (See FIGS. 2A and 3A).

Each jaw member 110, 120 include a tissue contacting surface 112, 122,respectively, disposed on an inner-facing surface thereof. Tissuecontacting surfaces 112 and 122 cooperate to grasp tissue positionedtherebetween and are configured to coagulate and/or seal tissue uponapplication of energy from generator 40. Tissue contacting surfaces 112and 122 may be further configured to cut tissue and/or configured toposition tissue for cutting after tissue coagulation and/or tissuesealing is complete. One or more of the tissue contacting surfaces 112,122 may form part of the electrical circuit that communicates energythrough the tissue held between the upper and lower jaw members 110 and120, respectively.

Trigger assembly 30 is configured to actuate a knife (e.g., knifeassembly 186, See FIG. 2B) disposed within forceps 10 to selectivelycut/sever tissue grasped between jaw members 110 and 120 positioned inthe first condition. Switch 32 is configured to selectively provideelectrosurgical energy to end effector assembly 100.

Referring now to FIG. 1B, an open forceps 10′ is depicted and includesend effector 100′ attached to a handle assembly 22′ that includes a pairof elongated shaft portions 12 a′ and 12 b′. Each elongated shaftportion 12 a′, 12 b′ include a respective proximal end 14 a′, 14 b′ anda distal end 16 a′, 16 b′. The end effector assembly 100′ includes upperand lower members 110′, 120′ formed from, or attached to, eachrespective distal end 16 b′ and 16 a′ of shafts 12 b′ and 12 a′. Shafts12 a′ and 12 b are attached via pivot 19′ and are configured to pivotrelative to one another thereby actuating the jaw members 110′, 120′between the first condition and the second condition, as describedhereinabove.

Shafts 12 a′ and 12 b′ include respective handles 17 a′ and 17 b′disposed at the proximal ends 14 a′ and 14 b′ thereof. Handles 17 a′ and17 b′ facilitate scissor-like movement of the shafts 12 a′ and 12 b′relative to each other, which, in turn, actuate the jaw members 110′ and120′ between a first condition and a second condition. In the firstcondition, the jaws 110′ and 120′ cooperate to grasp tissue therebetweenand, in a second condition, the jaw members 110′ and 120′ are disposedin spaced relation relative to one another.

In some aspects, one or more of the shafts, e.g., shaft 12 a′, includesa switch assembly 32′ configured to selectively provide electricalenergy to the end effector assembly 100′. Forceps 10′ is depicted havinga cable 34′ that connects the forceps 10′ to generator 40 (as shown inFIG. 1). Switch assembly 32′ is configured to selectively delivery theelectrically energy from the generator 40 to the seal plates (notexplicitly shown, see seal plates 112, 122 in FIGS. 2A and 2B). Switchassembly 32′ may also be configured to select the electrosurgical energydelivery mode and/or the delivery sequencing as will be discussedhereinbelow.

Trigger assembly 30′ is configured to actuate a knife assembly 186, asdescribed with respect to FIG. 2B hereinbelow, disposed within forceps10′. The proximal end of the knife assembly 186 (See FIG. 2B) connectsto trigger assembly 30′ within the shaft 12 b′ of the forceps 10′. Knifeassembly 186 extends through shaft 12 b′ and forms a distal cutting edge184 on the distal end thereof (See FIG. 2B). Knife assembly 186, whenactuated by trigger assembly 30′, extends the distal cutting edge 184distally through a knife channel 115 (see FIGS. 2A and 2B) to severtissue positioned between the jaw members 110′ and 120′.

With reference to FIGS. 2A and 2B, knife channel 115 is defined by achannel formed within one or both jaw members 110 and 120 to permitreciprocation of knife assembly 186 therethrough, e.g., via activationof the trigger assembly 30, 30′ (See FIGS. 1A and 1B). The upper jawmember 110 and the lower jaw member 120, while in a first condition asillustrated in FIG. 2B, form knife channel 115 therebetween. Knifechannel 115 includes an upper knife channel 115 a, formed in the upperjaw member 110, mated with a lower knife channel 115 b, formed in thelower jaw member 120.

Each seal plate 112, 122 may form a planar sealing surface that includesa plurality of seal plate segments 112 a-112 c and 122 a-122 c,respectively, electrically isolated from each other by insulatingmembers 125 a, 125 b. Each seal plate segment 112 a-112 c and 122 a-122c may form a substantially equal portion of the sealing surface (seeFIG. 3A) or seal plate segments 112 a-112 c and 122 a-122 c may beunequally apportioned (see FIG. 2A).

Insulating members 125 a and 125 b may be formed from any suitableinsulating material or dielectric material that provides electricalisolation between the middle seal plate segments 112 b and 122 b and theinner and outer seal plate segments 112 a, 122 a and 112 c, 122 c,respectively. Insulating members 125 a and 125 b may be formed from apolytetrafluorethylene (PTFE), polypropylene,polychiorotrifluoroethylene (IPCTFE), polyethylene,polyethyleneterephthalate (PET), polyvinylchloride (PVC), a ceramicmaterial or even air in a gap formed between adjacent seal segments.

The individual seal plate segments 112 a-112 c and 122 a-122 c may bepre-selected, or dynamically selected, as part of one or more electricalcircuits that deliver electrosurgical energy to tissue positionedbetween the jaw members 110 and 120. For example, in one configurationthe end effector 100 may include a first bipolar circuit that includesthe outer seal plate segments 112 a and 122 a, a second bipolar circuitthat includes the middle seal plate segments 112 b and 122 b and a thirdbipolar circuit that includes the inner seal plate segments 112 c and122 c wherein the first, second and third bipolar circuits areindependently enabled and/or controlled to deliver electrosurgicalenergy to tissue.

The seal plate segments on each jaw (e.g., lower seal plate segments 122a-122 c on lower jaw 120) are arranged such that the seal plate segmentsare positioned radially outward from the lower knife channels 115 b in astep-like manner. In this embodiment each seal plate segment forms aradius on the distal end thereof, thereby extending proximally alongeach side of the upper and lower jaw members 110 and 120. The seal platesegments 112 a-112 c on the upper seal plate 112 may have correspondingseal plate segments 122 a-122 c on the lower seal plate 122 positionedoppose and one another, as illustrated in FIG. 2B.

As shown by the cross-section of the end effector 100 in FIG. 2B, theinner surface of the seal plates 112 and 122 are each disposed on a sealplate mount 114 and 124, respectively. Each seal plate mount 114 and 124may be formed as part of each seal plate 112 and 122, formed as part ofthe each jaw housing 110 a and 120 a or formed as separate componentseach configured to interconnect the seal plate 112 and 122 with therespective jaw housing 110 a and 120 a. Seal plate mount 114 and 124 mayinclude a circuit, circuit board and/or connections that connects theseal plate segments (e.g., 112 a-112 c and 122 a-122 c) to the source ofelectrical energy (e.g., generator 40, See FIG. 1). Circuit, circuitboard or connections may further include one or more switches (Seemultiplexer 60 in FIG. 6 and described hereinbelow) configured toselectably connect one or more seal plate segments 112 a-112 c and 122a-122 c to the generator 40. The one or more switches may be controlledby the generator 40 or controlled/selected by the clinician (e.g.,through the generator 40, the switch 32, switches in the seal platesegments or additional switching or selecting mechanisms on or in theforceps 10, 10′).

In another embodiment, seal plates 112 and 122 mount directly to therespective jaw housing 110 a and 120 a and an electrical connection fromthe generator 40 connects directly to each seal plate segment 112 a-112c and 122 a-122c. A control circuit (See control circuit 42 in FIG. 6)may be configured to selectively form one or more electrosurgical energydelivery circuits with one or more of the seal plate segments 112 a-112c and 122 a-122 c. The selected seal plate segments 112 a-112 c and 122a-122 c can be configured to deliver electrosurgical energy to tissue ina monopolar or bipolar manner. As illustrated in FIG. 6, control circuit42 may be housed in the generator 40 as stand-alone hardware or thefunctionality may be incorporated into the generator's 40 existingcircuitry. Alternatively, as discussed hereinabove, the control andselection functionality described herein may be incorporated into theforceps 10.

The control circuit (e.g., controller 42; See FIG. 6) may be configuredto dynamically select one or more of the seal plate segments 112 a-112 cand 122 a-122 c before and/or during the surgical procedure and may beconfigured to dynamically switch the selected seal plate segments 112a-112 c and 122 a-122 c that form one or more of the electrosurgicalenergy delivery circuits. More specifically, the control circuit (e.g.,controller 42) may be configured to provide electrosurgical energy tothe first bipolar circuit during a first treatment cycle, configured toprovide electrosurgical energy to the second bipolar circuit during asecond treatment cycle and configured to provide electrosurgical energyto the third bipolar circuit during a third treatment cycle.

In another embodiment, the selected bipolar circuit does not include acorresponding seal plate segment on the upper and lower jaw members 110and 120. For example, the bipolar circuit may include the outer sealsegment 112 a on the upper jaw member 110 and the middle and/or innerseal plate segment 122 b and 122 c on the lower jaw member 120 (See FIG.2A). By forming a bipolar circuit in this manner (i.e., by not selectingcorresponding seal plate segments on the upper and lower jaw members110, 120) contact between the upper seal plate 112 and the lower sealplate 122 will not result in a short circuit between the selectedportions of the upper and lower jaw members 110 and 120. As such, a stopmember (not shown) that typically maintains a gap between the innersurface of the seal plates 112 and 122 and prevents contact between theseal plates 112 and 122 may not be required since contact between theseal plates 112 and 122 will not result in a short-circuit conditiontherebetween.

In another embodiment, the seal plate segments 112 a-112 c and 122 a-122c selected to form a bipolar circuit are determined by a measured tissueparameter, wherein the measured tissue parameter is related to tissuepositioned between the upper jaw member 110 and the lower jaw member120. For example, the generator 40 (e.g., controller, 42 sensor module48 and multiplexer 60) may be configured to measure the impedance oftissue positioned between two selected seal plate segments (e.g., upperseal plate segments 112 a-112 c and/or lower seal plate segments 122a-122 c). Based on the measured value, the generator 40 may form one ormore bipolar circuits between selected seal plate segments (e.g., upperseal plate segments 112 a-112 c and/or lower seal plate segments 122a-122 c). The generator 40 may also generate an energy delivery sequencewherein the seal plate segments that form part of the one or morebipolar circuits are dynamically selected based on one or more measuredtissue parameters. The generator 40 may also be configured to perform asubsequent measurement after energy delivery is initiated.

Generator 40 may perform a series of impedance measurements between theseal plate segments (e.g., upper seal plate segments 112 a-112 c and/orlower seal plate segments 122 a-122 c). The measurements may form atissue impedance profile of the tissue positioned between the upper andlower jaw members 110 and 120. The tissue impedance profile may beutilized by the generator 40 to determine an energy delivery sequencespecific to the tissue positioned between the upper and lower jawmembers 110 and 120.

In another embodiment, seal plate segments 112 a-112 c and 122 a-122 cmay be configured to energize from an outside-to-inside direction orfrom an inside-to-outside direction. For example, outer seal platesegments 112 a and 122 a may be initially energized for a firstenergization period, followed by a subsequent energization periodwherein the middle seal plate segments 112 b and 122 b and/or the innerseal plate segments 112 c and 122 c are energized.

FIGS. 3A and 3B illustrate a multi-circuit end effector assembly 300according to another embodiment of the present disclosure. The endeffector assembly 300 includes a pair of opposing jaw members 310 and320 and opposing seal plates 312 and 322 housed in upper and lower jawhousings 310 a and 320 a, respectively. Upper and lower seal plates 312and 322 each include a plurality of seal plate segments 312 a-312 e and322 a-322 e, respectively, arranged on the inner surface of the sealplates 312 and 322, extending longitudinally along a substantial portionof the length of the jaw members 310 and 320 and parallel thelongitudinal centerline X-X. Each seal plate 312, 322 forms a sealingsurface (or substantially planar sealing surface) and includes aplurality of seal plate segments 312 a-312 e and 322 a-322 e,respectively, electrically isolated from each other by insulatingmembers 325 a and 325 b. The seal plate segments 312 a-312 e and 322a-322 e may form substantially equal or unequal portions of the sealingsurface.

Seal plate segments 312 a-312 e and 322 a-322 e may be mounted on arespective seal plate mounts 314 and 324. Seal plate mount 314 and 324may be formed as part of each respective seal plate 312 and 322, formedas part of each respective jaw housing 310 a and 320 a or configured tointerconnect each seal plate 312 and 322 with the respective jaw housing310 a and 320 a. Seal plate mount 314 and 324 may include a circuit orcircuit board that provides an electrical connection to one or more ofthe seal plate segments (e.g., upper seal plate segments 312 a-312 e,lower seal plate segments 322 a-322 e). Seal plate mount 314 and 324and/or circuit (or circuit board) formed therein provide an electricalconnection between the source of electrical energy (e.g., generator 40,See FIG. 1) and the seal plates 312 and 322.

Seal plates 312 and 322 and/or seal plate mounts 314 and 324 may includeone or more switches (not explicitly shown) configured to selectablyconnect one or more seal plate segments 312 a-312 e and 322 a-322 e tothe source of electrical energy (e.g., generator 40 in FIG. 1;multiplexer 60 in FIG. 6). Switches may be automatically controlled bythe generator 40 or selectable by the clinician through the generator 40or through a switch (e.g., switch 32 or selector switch (not explicitlyshown) formed on or in housing 20).

In one embodiment, the seal plate segments 312 a-312 e and 322 a-322 eare energized from an outside-to-inside manner or from aninside-to-outside manner. For example, corresponding upper and lowerouter seal plate segments 312 a and 322 a, 312 e and 322 e may beinitially energized for a first energization period, followed by asubsequent energization period wherein any one or more of the interiorseal plate segments 312 b-312 d and 322 b-322 d, or combination thereof,are energized.

In a further embodiment, the upper and lower middle seal plate segments312 c and 322 c may be configured to cut tissue positioned therebetweenand the upper and lower outer seal plate segments 312 a, 312 b, 313 d,312 e and 322 a, 322 b, 322 d, 322 e, respectively, are configured toseal tissue. The generator 40 may be configured to provideelectrosurgical energy to seal tissue during a seal sequence andelectrosurgical energy to cut tissue during a cut sequence. During theseal sequence, the generator 40 may provide an electrosurgical energysignal to select upper and lower seal plate segments 312 a-312 e and 322a-322 e to coagulate and seal tissue. During a subsequent cut sequence,the generator 40 may provide an electrosurgical energy signal to theupper and lower middle seal plate segments 312 c and 322 c to cut tissuepositioned therebetween. Providing a multi-circuit end effector 300capable off electrosurgically sealing tissue during a first energydelivery period and capable of electrosurgical cutting tissue during asecond energy delivery period eliminates the need for providing a meansfor mechanical cutting tissue (i.e., elimination of the trigger assembly30′ and knife assembly 186 of forceps 10′, See FIGS. 1 and 2).

FIGS. 4A and 4B illustrate a multi-circuit end effector assembly 400according to a further embodiment of the present disclosure wherein theend effector assembly 400 includes a pair of opposing jaw members 410and 420 and opposing seal plates 412 and 422 housed in upper and lowerjaw housing 410 a and 420 a, respectively. Upper and lower seal plates412 and 422 each include a plurality of seal plate segments 412 a-412 eand 422 a-422 e, respectively, arranged on the inner surface of the sealplates 412 and 422, extending the length of the jaw members 310 and 320and parallel the longitudinal centerline X-X. Each seal plate 412 and422 forms a sealing surface and includes a plurality of seal platesegments 412 a-412 e and 422 a-422 e, respectively, electricallyisolated from each other by insulating members 425 a and 425 b. Eachseal plate segment 412 a-412 e and 422 a-422 e may form a substantiallyequal or unequal portion of the sealing surface.

The upper or lower middle seal plate segments 412 c and 422 c mayinclude a geometry configured to facilitate tissue cutting, in additionto tissue sealing, while the remaining outer seal plate segments 412 a,412 b, 412 d, 412 e and 422 a, 422 b, 422 d, 422 e may include ageometry configured to facilitate tissue sealing. In this aspect, thelower middle seal plate segment 422 c forms a ridge “R” wherein theridge “R” is raised with respect to the sealing surface to facilitatetissue cutting during a second energization period as discussed abovewith respect to FIGS. 3A and 3B.

Upper and lower middle seal plate segments 412 c and 422 c may beincluded in a tissue sealing circuit in an initial tissue sealing stageand may form a tissue cutting circuit in a subsequent tissue cuttingstage. For example, in an initial tissue sealing stage the upper middleseal plate segment 412 c may form a sealing circuit with outer sealplate segment 412 a and 422 a and lower middle seal plate segment 412 cmay form a sealing circuit with the outer seal plate segments 412 e and422 e. The sealing stage may include the selection of additional sealingcircuits that may or may not include the upper and lower middle sealplate segments 412 c and 422 c. After the sealing stage is complete andthe tissue positioned between the upper and lower jaws members 410 and420 has been sufficiently sealed, a tissue cutting circuit that includesthe upper and lower middle seal plate segments 412 c and 422 c isselected and upon activation thereof cuts the tissue positionedtherebetween.

In a further embodiment, geometry, similar to the ridge “R” formed onthe lower middle seal plate segment 422 c of FIGS. 4A and 4B, forms aridge on the upper and lower middle seal plate segments 412 c and 422 cwherein the geometries interface one another to facilitate cutting ofthe tissue positioned therebetween. For example, the upper and lowermiddle seal plate segments 412 c and 422 c may be arranged such that thegeometry on each surface mates with the other along the inner-mostsurfaces or ridges. In a further embodiment, the upper and lower middleseal plate segments 412 c and 422 c include respective geometries thatform a shearing interface therebetween thereby elimination or reducingthe need for the tissue to be electrically energized to cut.

FIGS. 5A and 5B illustrate a multi-circuit end effector assembly 500,similar to the multi-circuit end effector of FIGS. 4A-4B, wherein thegeometry of the lower middle seal plate segment 522 c includes a curvedinner-most surface that is raised with respect to the sealing plate 522to facilitate the cutting of tissue during a second energization periodas discussed above with respect to FIGS. 3A and 3B. In a furtherembodiment the upper and lower middle seal plate segments 512 c and 522c both include interfacing curved surfaces on the inner-most surfacesthereof.

As illustrated in FIGS. 4A-4B and 5A-5B, the geometry formed on theinner surface of the middle seal plate segments 422 c, 522 c provides aminimum separation distance between the upper and lower seal plates 412and 422, 512 and 522, and is configured to seal tissue by deliveringelectrosurgical energy in an initial sealing stage and is configured tocut tissue by delivering electrosurgical energy in a subsequent tissuecutting stage.

In FIG. 6 a system schematic block diagram for driving an end effectoraccording to the present disclosure is indicated as system 1000. System1000 includes a generator 40, a forceps 10 with a multi-circuit endeffector 100 connected by a cable 34. The generator 40 includes acontroller 42, a power supply 44, an RF output stage 46, a sensor module48 and a multiplexer 60. The power supply 44 provides DC power to the RFoutput stage 46 that converts the DC power into one or more RF energysignals. The one or more RF energy signals are individually provided tothe multiplexer 60.

The controller 42 includes a microprocessor 50 having a memory 52 whichmay be volatile type memory (e.g., RAM) and/or non-volatile type memory(e.g., flash media, disk media, etc.). The microprocessor 50 includes aconnection to the power supply 44 and/or RF output stage 46 that allowsthe microprocessor 50 to control the output of the generator 40according to an open-loop and/or closed-loop control scheme. The powersupply 44, RF output stage 46, multiplexer 60 and sensor module 48 areconnected to, and controlled by, the controller 42 and configured tooperate in concert to perform a selected surgical procedure.

For example, controller 42 may instruct the multiplexer 60 to connect anRF energy signal generated by the RF output stage 46 between any two ormore segments of the end effector 100. For example, multiplexer 60 maybe instructed by the controller 42 to form an electrosurgical energydelivery circuit between with outer seal segment 112 a on the upper jawmember 110 and the inner seal portion 122 c on the lower jaw member 120(See FIG. 2A). Additionally, controller 42 may instruct the multiplexer60 to connect the sensor module 48 between any two or more segments ofthe end effector 100 and controller 42 may instruct the sensor module 48to perform a measurement between the selected segments of the endeffector 100. For example, multiplexer 60 may be instructed by thecontroller 42 to form a measurement circuit between the middle sealplate segment 112 b on the upper jaw member 110 and the middle sealplate segment 122 b on the lower jaw member 120 (See FIG. 2A).Controller 42 may issue instructions to the various components in thegenerator 40 to performed energy delivery and measurements sequentiallyor simultaneously.

In a further embodiment, during operation the controller 42 may instructthe multiplexer 60 to direct an RF energy signal, generated by the RFoutput stage 46, to each of the first, second and third circuits duringthe respective first, second and third treatment cycles. The first,second and third treatment cycles may be executed consecutively,simultaneously or any portion of a treatment cycle may overlap with anyother treatment cycle.

Controller 42, in executing a closed-loop control scheme, may instructthe multiplexer 60 to simultaneously connect two segments on the endeffector 100 to the RF output stage 46 for delivery of electrosurgicalenergy and may further instruct the multiplexer to connect the sensormodule 48 to two segments on the end effector 100 wherein the sensormodule 48 provides feedback to the controller 42 for an energy deliverycontrol loop (i.e., the sensor module 48 includes one or more sensingmechanisms/circuits for sensing various tissue parameters such as tissueimpedance, tissue temperature, output current and/or voltage, etc.). Thecontroller 42, using the energy delivery control loop, signals the powersupply 44 and/or RF output stage 46 to adjust the electrosurgical energysignal.

The controller 42 also receives input signals from the input controls ofthe generator 40 and/or forceps 10, 10′. The controller 42 utilizes theinput signals to generate instructions for the various components in thegenerator 40, to adjust the power output of the generator 40 and/or toperform other control functions. The controller 42 may include analogand/or logic circuitry for processing input signals and/or controlsignals sent to the generator 40, rather than, or in combination with,the microprocessor 50.

The microprocessor 50 is capable of executing software instructions forprocessing data received by the sensor module 48, and for outputtingcontrol signals to the generator 40, accordingly. The softwareinstructions, which are executable by the controller 42, are stored inthe memory 52 of the controller 42.

The sensor module 48 may also include a plurality of sensors (notexplicitly shown) strategically located for sensing various propertiesor conditions, e.g., tissue impedance, voltage (e.g., voltage at thegenerator 40 and/or voltage at the tissue site) current (e.g., currentat the generator 40 and/or current delivered at the tissue site, etc.)The sensors are provided with leads (or wireless) for transmittinginformation or signals to the controller 42. The sensor module 48 mayinclude control circuitry that receives information and/or signals frommultiple sensors and provides the information and/or signals, and/or thesource of the information (e.g., the particular sensor providing theinformation), to the controller 42.

The sensor module 48 may include a real-time voltage sensing system anda real-time current sensing system for sensing real-time values relatedto applied voltage and current at the surgical site. Additionally, anRMS voltage sensing system and an RMS current sensing system may beincluded for sensing and deriving RMS values for applied voltage andcurrent at the surgical site.

The generator 40 includes suitable input controls (e.g., buttons,activators, switches, touch screen, etc.) for controlling the generator40, as well as one or more display screens for providing the surgeonwith information (e.g., intensity settings, treatment completeindicators, etc.). The controls allow the surgeon to adjust power of theRF energy, waveform, and other parameters to achieve the desiredwaveform suitable for a particular task (e.g., surgical procedure suchas tissue ablation, coagulation, cauterization, resection or anycombination thereof). Further, the forceps 10, 10′ may include one ormore input controls, some of which may be redundant, with certain inputcontrols included in the generator 40. Placing select input controls atthe instrument 10, 10′ allows for easier and faster modification of RFenergy parameters during the surgical procedure without requiringinteraction with the generator 40.

The generator 40 may be configured to perform monopolar and/or bipolarelectrosurgical procedures. As illustrated in FIG. 6, multiplexer 60 maybe configured to connect to a return electrode 55 thereby providing areturn path for current during a monopolar energy delivery procedurewherein energy is delivered through one or more selected segments on theend effector 100 in a monopolar manner. The generator 40 may alsoinclude a plurality of inputs and/or outputs for interfacing withvarious electrosurgical instruments (e.g., footswitch, selector forselecting various electrosurgical modes such as cutting, blending,division, etc. and selector for selecting various procedures such asmonopolar, bipolar, vessel sealing and ablation).

In any of the above-described embodiments, the seal plates or any sealplate segment thereof may be configured to seal sense and/or cut anytype of tissue. In addition, any of the end effector assembliesdescribed above may be configured to cut tissue with or without a knife.

With respect to sealing tissue, the gap between the seal plates (e.g.,seal plates 112 and 122, see FIG. 2B) may be controlled by one or morestop members (not explicitly shown) on the inner surface thereof.Alternatively, the gap between the seal plates 412 and 422, 512 and 522may also be controlled by the geometry of the Ridge “R” formed on themiddle seal plate segment 422 c and 522 c. In addition, one or moredevices, e.g., resilient members or the like, may be utilized to provideand/or control an appropriate pressure between the jaw members when thejaw members are in the clamping configuration. Further, one or moredevices operably associated with the forceps 10 and 10′ and/or thegenerator 40 may be configured to the control the amount ofelectrosurgical energy provided to the jaw members during a sealingstage, a cutting stage or during a stage that performs simultaneoussealing and cutting.

In another embodiment, seal plates according the present disclose may beconfigured to heat tissue. For example, seal plate assembly may beconfigured to include resistive heating capabilities instead of, or inaddition to electrosurgical energy delivery capabilities.

While several embodiments of the disclosure have been shown in thedrawings and/or discussed herein, it is not intended that the disclosurebe limited thereto, as it is intended that the disclosure be as broad inscope as the art will allow and that the specification be read likewise.Therefore, the above description should not be construed as limiting,but merely as exemplifications of particular embodiments. Those skilledin the art will envision other modifications and combinations of theembodiments described herein are within the scope and spirit of theinvention and the claims appended hereto.

What is claimed:
 1. An end effector assembly comprising: a pair ofopposing jaw members pivotably attached and moveable from a first spacedposition to a second grasping position, each jaw member including: a jawhousing; a seal plate formed on an inner surface of the jaw memberincluding at least two seal plate segments extending along a substantialportion of the length of the jaw members; and an insulating memberpositioned between adjacent seal plate segments and configured toprovide electrical isolation between adjacent seal plate segments,wherein each sealing plate segment is adapted to selectively connect toan electrosurgical energy source and form part of an electrosurgicalenergy delivery circuit.
 2. An end effector assembly according to claim1, wherein each jaw member further includes: a seal plate mountconfigured to operably couple the seal plate and the jaw housing andfurther configured to electrically couple each of the two or more sealplate segments to an electrosurgical energy source.
 3. An end effectorassembly according to claim 2, wherein the seal plate mount includes atleast one switch circuit board disposed on and operably coupled atop theseal plate.
 4. An end effector assembly according to claim 1, whereineach seal plate includes: a first seal plate segment, a second sealplate segment, a middle seal plate segment operably coupled between thefirst and second seal plate segment, within the seal plate, a firstinsulating member positioned between the first seal plate segment andthe middle seal plate segment and providing electrical isolationtherebetween, and a second insulating member positioned between thesecond seal plate segment and the middle seal plate segment andproviding electrical isolation therebetween. wherein the first, secondand middle seal plate segments on each opposing jaw member form a planarsealing surface.
 5. An end effector assembly according to claim 4,wherein the first seal plate segments, the second seal plate segmentsand the middle seal plate segment are configured to selectively formpart of an electrosurgical energy delivery circuit for sealing tissuepositioned between the pair of opposing jaw members.
 6. An end effectorassembly according to claim 5, wherein each middle seal plate segment isconfigured to form part of an electrosurgical energy delivery circuitfor cutting tissue positioned between the pair of opposing jaw members.7. An end effector assembly according to claim 4, wherein at least oneof the middle seal plate segments include a geometry that is raised withrespect to the planar sealing surface.
 8. An end effector assemblyaccording to claim 7, wherein the geometry is selected from a ridge anda surface including a radius of curvature.
 9. An end effector assemblyaccording to claim 4, wherein the first seal plate segment, the secondseal plate segment and the middle seal plate segment on each of the sealplates extends longitudinally along a substantial portion of thecorresponding jaw member.
 10. An electrosurgical instrument, comprising:a housing; a handle assembly; a shaft having a proximal and distal end,the proximal end operably coupled to the housing; an end effectorassembly operably coupled to the distal end of the shaft, the endeffector assembly comprising: pair of opposing jaw members pivotablyattached and moveable from a first spaced position to a second graspingposition, each jaw member including: a jaw housing; a seal plate formedon an inner surface of the jaw member including at least two seal platesegments extending along a substantial portion of the length of the jawmembers; and an insulating member positioned between adjacent seal platesegments and configured to provide electrical isolation between adjacentseal plate segments, wherein each sealing plate segment is adapted toselectively connect to an electrosurgical energy source and form part ofan electrosurgical energy delivery circuit.
 11. An electrosurgicalinstrument according to claim 10, wherein the electrosurgical instrumentfurther includes: a seal plate mount formed on each of the pair ofopposing jaw members, the seal plate mount configured to operably couplethe seal plate and the jaw housing and further configured toelectrically couple each of the two or more seal plate segments to anelectrosurgical energy source.
 12. An electrosurgical instrumentaccording to claim 11, wherein the electrosurgical instrument furtherincludes: a switch formed in the housing and operably coupled to theseal plate mount; wherein the seal plate mount further includes acircuit board including at least two circuit board switches operablycoupled to the switch, the switch and two circuit board switchesconfigured to selectively couple the at least two seal plate segments tothe electrosurgical energy source.
 13. An electrosurgical instrumentaccording to claim 10, wherein each seal plate includes: a first sealplate segment; a second seal plate segment; a middle seal plate segmentoperably coupled between the first and second seal plate segment, withinthe seal plate; a first insulating member positioned between the firstseal plate segment and the middle seal plate segment and providingelectrical isolation therebetween; and a second insulating memberpositioned between the second seal plate segment and the middle sealplate segment and providing electrical isolation therebetween, whereinthe first seal plate segment, the second seal plate segment and themiddle seal plate segment on each opposing jaw member form a planarsealing surface.
 14. An electrosurgical instrument according to claim13, wherein the electrosurgical instrument further includes: a switchformed in the housing, the switch operably coupled to the seal plate;wherein the switch is configured to selectively couple at least two ofthe at least two seal plate segments to the electrosurgical energysource.
 15. An electrosurgical instrument according to claim 13, whereinthe first seal plate segment, the second seal plate segment and themiddle seal plate segment are configured to selectively form part of anelectrosurgical energy delivery circuit for sealing tissue positionedbetween the pair of opposing jaw members.
 16. An electrosurgicalinstrument according to claim 15, wherein each middle seal plate segmentis configured to form part of an electrosurgical energy delivery circuitfor cutting tissue positioned between the pair of opposing jaw members.17. An electrosurgical instrument according to claim 16, wherein atleast one of the middle seal plate segments include a geometry that israised with respect to the planar sealing surface.
 18. Anelectrosurgical instrument according to claim 17, wherein the geometryis a ridge.
 19. An electrosurgical instrument according to claim 17,wherein the geometry includes a radius of curvature.
 20. Anelectrosurgical instrument according to claim 13, wherein each middleseal plate segment is configured to form part of an electrosurgicalenergy delivery circuit for cutting tissue positioned between the pairof opposing jaw members.